g-C3N4 Nanosheet Nanoarchitectonics: H2 Generation and CO2 Reduction

Few-layered graphitic carbon nitride (g-C3N4) has been considered a popular base for constructing composite materials in photocatalytic CO2 reduction and H-2 generation applications, particularly for constructing g-C3N4 based composites based on the idea of nanoarchitectonics. The photocatalytic activity of these constructed g-C3N4 composites relies on the composition, morphology, microstructure of the material. This review aims to focus on the summary of latest progress in the development of few-layered g-C3N4 nanosheets based noble metal clusters/nanoparticles and other semiconductor nanomaterials modified composite materials constructed using the technology of nanoarchitectonics for photocatalytic H-2 generation and CO2 reduction. This review covers a brief introduction of the enhanced photogenerated carrier separation and transfer as well as extended light absorption of superior thin g-C3N4 nanosheets based photocatalysts; discussions on the mechanism of g-C3N4 based photocatalyst involved photocatalytic H2O splitting and CO2 reduction system; the latest progress in the study of nanoarchitectonics of a variety of g-C3N4 based heterostructures including type II, Z-scheme, S-scheme, and Schottky junction. Major challenges on nanoarchitectonics of superior thin g-C3N4 based heterostructures, as well as the recommendations for future studies of these materials to attain higher efficiency in photocatalytic H-2 generation and CO2 reduction, are also concluded.